What is the Difference Between Testing for COVID-19 at Home vs. in a Clinic?

Testing for COVID-19, including at-home testing, is becoming increasingly common in a host of situations, from before gathering with friends and family and before traveling to entering restaurants in some areas. Many times, you simply want to err on the side of caution and make sure your symptoms are truly just a cold and not COVID. When it comes to the actual test, how do you know which is the best route for you? Here are the main testing options available right now:

PCR (polymerase chain reaction) Test

A PCR sample is collected by inserting a swab into the nostril and taking cells from the back of the nose, or sometimes through a saliva test. This test is performed by a health care provider if you have been exposed or if you are experiencing symptoms. It looks for genetic material from the virus in a patient’s sample.

The PCR test is the gold standard when it comes to COVID-19 testing. Results may be available in minutes if analyzed onsite or a soon as a few days if sent to an outside lab. PCR tests are very accurate when properly performed by a health care professional, whereas a rapid test can miss some cases.

There are also at-home PCR kits that, like the one used at a doctor’s office, collect a sample with a nasal swab. But, it is then mailed it to a laboratory to be analyzed. Because the results are mailed off, at-home PCR tests can typically take anywhere between three to seven days for results.

Rapid Antigen Tests

At-home tests are a good option for people who need to know right away if they have COVID-19. Many of them only test for antigens, so while they’re faster, they are less sensitive than a PCR test. They aren’t as effective at detecting COVID. Many healthcare providers also offer rapid antigen tests in person.

The rapid at-home antigen tests also use a nasal swab, detecting certain viral proteins in the sample in 15 minutes. These tests are can be purchased at a pharmacy and are faster and less expensive than PCR tests. Timing is key with these test results. For example, if you are going to an event, you should test on the day of the event because that’s going to give you the best information of whether you have high amounts of the virus in your system at that time.

A positive antigen test result is considered accurate when instructions are carefully followed, but there’s an increased chance of false-negative results. That means it’s possible to be infected with the virus but have a negative result.

Be sure to pay attention to the fine print when using an at-home COVID test. If you test negative but are still experiencing COVID symptoms, it’s best to follow up with an in-person PCR test.